In standard preparation installations of semiconductor components, the substrate to be treated, notably by epitaxy, is mounted generally horizontally inside the enclosure of a reaction oven on a graphite or other material support, called a susceptor. The substrate is positioned in place against motion by studs distributed on the support periphery. These studs have generally a projecting head bearing on the substrate edges while the axes of these studs, after having crossed the support, are stopped by metallic pins extending laterally through them. As a variant, the studs may be replaced by a circular crown coming to bear on the substrate periphery or by a ring which is screwed or locked on the support by a bayonet or similar system.
Yet, these solutions have disadvantages, notably due to the fact that the positioning of the substrate and its immobilization require relatively lengthy and delicate operations, in particular for mounting the studs or the support crown. On the other hand, with a bayonet ring, the substrate is not perfectly fixed with respect to the support.